Evaluation of suitability of grass species for dry conditions (water stress)

Abstract

Based on three-year results of a field experiment evaluating aboveground biomass production and the number of stems of above-ground shoots of grass species (Lolium perenne, Dactylis glomerata, Festuca pratensis) grown in a 200×200 mm layout in two water regime variants (normal and reduced - 50% of precipitation) and further in two variants of mowing intensity (meadow - 3 mowings, grazing - 5 mowings per year), the following has been ascertained. The most productive species on averages of the two moisture regimes is Dactylis glomerata, Lolium perenne and Festuca pratensis have fodder weight significantly lower by 20.8% and 22.6% (meadow var.) and 16.9% and 21.9% (grazing var.). Reduction of moisture significantly decreased the above ground biomass weight in case of meadow exploitation in Dactylis glomerata -41.2%, in Lolium perenne by -9.9% and in Festuca pratensis -33.5%. In case of grazing exploitation, the influence of "drought" on production was less pronounced. Dactylis glomerata provided the same output, in Lolium perenne there was a decrease of -15.7% and in Festuca pratensis -11.9%. Reduction of precipitation significantly decreased shoot formation particularly in case of meadow utilization in Lolium perenne -23.7%, Dactylis glomerata -34.7% and Festuca pratensis -20.5%. In case of grazing utilization, reduction in the number of pseudostems due to "drought" was lower - in the order of the above species - 27.1% - 4.6% - 9.6%. Generally, compared with meadow utilization, grazing utilization decreases fodder production in both moisture regimes and increases the number of above-ground shoots.